Ball and socket coupling



April 14, 1953 R. B. PALMER BALL AND SOCKET coUPLING Filed June 27. 1952 www INVENTOR RUSH B. PALMER,

ATTORNEYS Patented AprfI 14, v1953 ,UNITED STATE S PATENT OFFICE- BALL AND SOCKET ooUPLING Y Rush B. Palmer, Quincy, Fla. A 4 f' Application .mme 27, 1952, serial No. 295,960

This invention relates to trailer hitches and more particularly to a trailer hitch having means positively locking the ball of the hitch in the complementary socket against accidental displacement. l f

It is amongA the objects of the invention to provide an improved trailer hitch having a ball formation and a body of rigid and unitary construction providing .a socket receiving the ball formation to provide a universal joint connection between a towing and a trailer vehicle; which has a tong structure carried by the socket body and engageable with the ball formation to hold the latter in the socket and a pressure block disposed between the legs of the tong structure positivelyV solaims. (o1. 28o-33.17)

holding this structure in engagement with the v ball formation against the possibility of accidental release; which is easy to couple and uncouple and can be easily connected to a towing vehicle andto the tongue of a trailer Vehicle; and which is simple and durable in construction, economical to manufacture, and positive and effective in operation.

VOther objects and'advantages will become apparent from a consideration of the following description and theappended claims in conjunction with the accompanying drawing wherein:

Figure 1 is a front elevational view of a trailer hitch illustrative of the invention;

Figure 2 is a side elevational view; and

Figure 3 is a cross sectional view on the line 3-3 of Figure 2.

With continued reference to the drawing, the trailer-hitch comprises a first element, generally indicated at A, including a ball formation I0 of substantially spherical shape, a base II of partly conical shape joined at its smaller end to the ball formation I0 and projecting from the latter and a screw threaded stem I2 projecting from the larger end of the base II with its longitudinal center line extending substantially through the center 0f the ball formation Ill. A nut I3 is threaded onto the screw threaded stem I2 for securing the element A to a suitable structural element or bracket on a towing vehicle, The hitch further comprises a second element, generally indicated at B, including a tubular body I5 of cylindrical shape having external screw threads I6 at one end thereof and having a portion near its other end thickened and provided with a recess I1 of partly spherical shape to constitute a socket formation I8 which receives the ballv I0 of the element A. Y

The tubular body I5 is provided with diametri- :cally opposite Aapertures 20 anclr2| ata location .v

near the end thereof having the external screw thread I6 and apertured lugs 22 and 23 project 4radially from the body at diametrically opposite locations therearound between the apertures 20 and 2 I and the socket formation I8.

An elongated lever 24 is pivotally connected intermediate its length to the lug 22 by a pivot pin 25 extending through the apertures in the lug 22 and through a registering aperture in the lever 2li and extends longitudinally of the tubular body Vi5 from the aperture 20 to a location somewhat beyond the outer end of the socket formation I8. At its end adjacent the socket formation the lever ,24 is provided with a terminal formation 26 hav- "ing a surface of partly spherical shape engageable with the ball formation II) adjacent the base I i, as illustrated in Figure 2, and has at its other 4end an angularly offset end portion 2l which extends through the aperture 20 in the tubular body I5,

i A lever 28, similar tothe lever' 24, is pivotally connected intermediate its length to the lug 23 ,by a pivot pin 29 extending through vregistering .apertures in the lugs and a registering aperture in the lever and also extends longitudinally of the body I5 from the aperture 2I to a location somewhat outwardly of the outer end of the socket formation I8. At its end adjacent the socket formation I8 the lever 28 is provided with a terminal formation 30 having a surface of partly spherical shape engaging the ball I0 adjacent the base I I and in opposition to the terminal formation 26 on the lever 24 and has at its other end an angularly offset lend portion 3| extending through the aperture 2 I,

A block 32 0f cylindrical shape is slidably Ymounted within the tubular body I5 and is movable between a position in which it is disposed 'between the angularly offset end portions 21 and 3l of the levers 24 and 28, as illustrated in Figure 2,to positively hold the terminal formations 25 and 30 of the levers in engagement with the ball Vformation I0 and hold the ball formation in the socket recess I1, and a position in which it is clear of the angularly disposed end formations 2l' and 3! of the levers to free mthe levers for swinging movement about the pivot pins 25 and 29 in a direction separating the terminal formations 26 Aand 30 to release the ball formation l0 from the socket formation I8 in the body I 5.

An internally screw threaded, flange cap 33 vthreaded onto the screw threaded end of the body I5 andis provided with a central aperture 34. A stem 35 extends slidably through the aperture 34 in the cap 3.3 and is threaded at one end into a centrally disposed tapped hole in the pressure block 32. This stem is provided intermediate its length with an abutment collar 36 which engages the outer side of the cap 33 when the pressure block 32 is disposed between the angularly offset end portions 21 and 3I of the levers 24 and 28, as illustrated in Figure 3, and a coiled compression spring 31 surrounds the stem 35 between the pressure block 32A and the inner sideof the capl 33 and resiliently urges the pressure block to the above described position in which it is disposed between the angularly offset end portions 21 and 3l of the levers. A handle 38 is secured on the stern 35 at the end of the stem outside of the cap 33 andremote from the pressure block 32 for moving the pressure block 32 upwardly against the .forceofsprin'g 31 until it is moved away from the angularly disposed end portions 21 and 3| of the le'i'ferstoV thereby free the levers for pivotal movement about the lpivot pinsV 25 and 29, so thatthe terminal formations 2B and 30 of the levers 'can move away from eachother to release the ball formation It;

A bracket 401of channelshaped cross section is secured'at one end to the body I5 adjacent the thickened end portion of the bodyV and projects p'erpendicul'arly from the body in a radial direction to receive the frontend of a trailer tongue'.V This bracketisr'provided with spaced apart; apertures 4I' and'42'through which suitable bolts or pins may be extended to secure a trailer tonguev to the" bracket.

When the hitch is in' use, the stem I2 ofthe element A is disposed in a substantially vertical or upright position with the ball formation I at the upper end of thestem. The body I5 is also 4disposed in an upright, substantially vertical position with the socket formation I8 at its lower end and receiving the ball formation IU; The handle 38' is at the upper end oftheV body I5 and, when it is desired tocouple the hitch, the element B secured to the front end of the-trailer tongue is raised by the handle 38 and moved until the socket recess I1 is directly over the ball formation I0. The element'B vis then lowered and, since the block 32v is held in a position above the apertures 2D'and 2l, 'the terminalfformations andv 30 on the levers 24 and 28l will be forced apart'b'y the ball formation tu and'will slide over this ball 'formation to a position" adjacent the space IIS at 'the bottom of the ball formation. Upo'nrelease of 'the handle after the ball formation I0 is vseated in the recess: I1, the block 32 is moved downwardly by the spring 3.1" to a position between the endiportions 21 and 3I of the levers 24 and28, so that'the body Picannot lift olf theballformation Iii. The only strain on the levers 2.4 vand ,'23 is that incident'to holding the body I5 .down onthe ball I0, the towing force being transmittedlfrom the ball formation through they thickened lower end portion ofthe body I5 constituting the'socket VIiito the bracket 40. The terminal formations 2.5 andi are spaced from the base Hsufli'ciently to provide 'for the usualrocking movements between .the towing vehiclerand the trailer and the body I5`-is free to rotate around the'ball formation I3 in'- cident to turningmovements between thev towing vehicle or tractor. and the towed vehicle or trailer.

In order to uncouple tl-ie.olevice,.itV isnecessary merely to. raise.r the. unitV B`by the handle Y3l!` until thepressureblock 3`2.is moved upward'- ly away vfrom the endportio'n's 21 and`3l ofthe 4 levers 24 and 28, and the socket recess I1 is moved upwardly away from the ball formation I0 and the terminal formations 26 and 30 of the levers are also moved upwardly past the ball formation.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is, therefore,.to be considered in all respects as illustrative andy not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaningl and range of equivalency of the claims are, therefore, intended to be embraced therein. y

1. Atrailer hitch comprising a rst unit incl'u'ding a ball formation, a base of partly conical shape projecting from said ball formation and a screwf threaded stern projectingV from said base, anda second unit including a tubular body having in one end a socket formation providing a recessy of partly spherical shape opening to said one end ofsaid body and receiving said'ball formation; saidbody having diametrically opposite apertures near the-other end thereof, apertured lugs projecting from saidbody at diametrically opposite locations therearoundbetween said apertures and said socket formation, levers pivotally mounted intermediate'their lengths one 'on each of said lugs and extending longitudinally of said tubular body, terminal formations onsaid levers at the ends of the latter adjacent said socket formation engageable with said ball formation adjacent said ba'se to hold said'ball formation in socket recess, angularly, disposed end portions-on saidlevers at' the ends of the latter remote from said' socket formation extending one through each of the apertures in said tubular body, a biockslidable in said tubular body and movable between/a position in which it is disposed between the angularlyA` disposed end portions of said'levers to hold said terminal formations in engagement with said ball Vformation and aposition in which it is clear of said angularly disposed end portions to free said terminal formati-ons to move away from each other and release said ball formation from said socket, an apertured'cap ciosingithel other end of vsaid tubularv body, a stem secured atone endA to said Vblock and extending slidably through the`r aperture in saidcap, an abutment y'on said stem engaging'the outerv side 4of'saidcap Vwherrsaid lolock" is ldisposed betweenthe anguiarly oi'fs'et end portionsofsaid levers, a spring'dispose'dbetween saidbl'ock and Vsaid 'cap `r'esilientiy, urging` said 'block to its` positionbet'ween'the' angul'arly offset endportions io'f said levers, a handle on'the end` of'said stem A remote from said `lolockfor"rr'ianually moving said blockaway from saidpo'sitionagainstthe'vforce of'rsaid spring, and' a bracket on said' tubular body intermediate the length of the latter'for connectir'ig said tubular body to the front end of the-tongue'of'A a trailer vehicle;

1 2. A trailer'hitoh comprising` agfirst unit' including a ball formation and a` screw threaded stem projectiiig from said ball formation, anda second i unit including a tubularA` body having'v in one end aA socket formation' receiving; said'ball formationA and apertures nearthe other end thereof, lugs" projecting from* said bodyw between said apertures and said socket formation', levers pivotally mountedintermediatetheir lengths one on each ofsaidlugs'and extending-longitudinally of said tubular body, terminal formations on said levers at the ends of the latter adjacent said socket formation engageable with said ball formation to hold the latter in said socket, angularly disposed end portions on said levers at the ends of the latter remote from said socket formation extending one through each of the apertures in said tubular body, a block slidable in said tubular body and movable between a position in which it is disposed between the angularly disposed end portions of said levers to hold said terminal formations in engagement with said ball formation and a position in which it is clear of said angularly disposed end portions to free said terminal formations to move away from each other and release said ball formation from said socket, means secured to said block for manually moving the latter from the rst mentioned to the last mentioned of said positions, spring means acting between said block and said body resiliently urging said block from said last mentioned to said first mentioned position, and a bracket on said tubular body adjacent said socket formation for connection to the f-ront end of the tongue of a trailer vehicle.

3. A trailer hitch comprising a first unit includin a ball formation and a screw threaded stem projecting from said ball formation, and a second unit including a tubular body having in one end a socket formation receiving said ball formation and apertures near the other end thereof, lugs projecting from said body between said apertures and said socket formation, levers pivotally mounted intermediate their lengths one on each of said lugs and extending longitudinally of said tubular body, terminal formations on said levers at the ends of the latter adjacent said socket formation engageable with said ball formation to hold the latter in said socket, angularly disposed end portions on said levers at the ends of the latter remote from said socket formation extending one through each of the apertures in said tubular body, a block slidable in said tubular body and movable between a iirst position in which it is disposed between the angularly disposed end portions of said levers to hold said terminal formations in engagement with said ball formation and a second position in which it is clear` of said angularly disposed end portions to free said terminal formations to move away from each other and release said ball formation from said socket, an apertured cap closing the other end of said tubular body, a stem secured at one end to said block and extending slidably through the aperture in said cap, an abutment on said stem engaging the outer side of said cap when said block is in said first position, a spring disposed, between said block and said cap resiliently urging said block to said rst position, a handle on the end of said stem remote from said block for manually moving said block from said rst to said second position against the force of said spring, and a bracket on said tubular body and projecting substantially perpendicularly therefrom for connecting said body to the front end of the tongue of a trailer vehicle.

RUSH B. PALMER.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 2,292,751 Forney Aug. 11, 1942 2,458,209 Sawatzki Jan. 4, 1949 FOREIGN PATENTS Number Country Date 104,206 Sweden Apr. 7, 1942 

